Congenital hepatic fibrosis in autosomal recessive polycystic kidney disease

ZFYVE19 deficiency: a ciliopathy involving failure of cell division, with cell death

BACKGROUND AND AIMS

Variants in ZFYVE19 underlie a disorder characterised by progressive portal fibrosis, portal hypertension and eventual liver decompensation. We aim to create an animal model to elucidate the pathogenic mechanism.

METHODS

Zfyve19 knockout (Zfyve19-/- ) mice were generated and exposed to different liver toxins. Their livers were characterised at the tissue, cellular and molecular levels. Findings were compared with those in wild-type mice and in ZFYVE19-deficient patients. ZFYVE19 knockout and knockdown retinal pigment epithelial-1 cells and mouse embryonic fibroblasts were generated to study cell division and cell death.

RESULTS

The Zfyve19-/- mice were normal overall, particularly with respect to hepatobiliary features. However, when challenged with α-naphthyl isothiocyanate, Zfyve19-/- mice developed changes resembling those in ZFYVE19-deficient patients, including elevated serum liver injury markers, increased numbers of bile duct profiles with abnormal cholangiocyte polarity and biliary fibrosis. Failure of cell division, centriole and cilia abnormalities, and increased cell death were observed in knockdown/knockout cells. Increased cell death and altered mRNA expression of cell death-related signalling pathways was demonstrated in livers from Zfyve19-/- mice and patients. Transforming growth factor-β (TGF-β) and Janus kinase-Signal Transducer and Activator of Transcription 3 (JAK-STAT3) signalling pathways were upregulated in vivo, as were chemokines such as C-X-C motif ligands 1, 10 and 12.

CONCLUSIONS

Our findings demonstrated that ZFYVE19 deficiency is a ciliopathy with novel histological features. Failure of cell division with ciliary abnormalities and cell death activates macrophages and may thus lead to biliary fibrosis via TGF-β pathway in the disease.

Global Transcriptomics of Congenital Hepatic Fibrosis in Autosomal Recessive Polycystic Kidney Disease using PCK rats

Congenital hepatic fibrosis / Autosomal recessive polycystic kidney disease (CHF/ARPKD) is an inherited neonatal disease induced by mutations in the PKHD1 gene and characterized by cysts, and robust pericystic fibrosis in liver and kidney. The PCK rat is an excellent animal model which carries a Pkhd1 mutation and exhibits similar pathophysiology. We performed RNA-Seq analysis on liver samples from PCK rats over a time course of postnatal day (PND) 15, 20, 30, and 90 using age-matched Sprague-Dawley (SD) rats as controls to characterize molecular mechanisms of CHF/ARPKD pathogenesis. A comprehensive differential gene expression (DEG) analysis identified 1298 DEGs between PCK and SD rats. The genes overexpressed in the PCK rats at PND 30 and 90 were involved cell migration (e.g. Lamc2, Tgfb2 , and Plet1 ), cell adhesion (e.g. Spp1, Adgrg1 , and Cd44 ), and wound healing (e.g. Plat, Celsr1, Tpm1 ). Connective tissue growth factor ( Ctgf ) and platelet-derived growth factor ( Pdgfb ), two genes associated with fibrosis, were upregulated in PCK rats at all time-points. Genes associated with MHC class I molecules (e.g. RT1-A2 ) or involved in ribosome assembly (e.g. Pes1 ) were significantly downregulated in PCK rats. Upstream regulator analysis showed activation of proteins involved tissue growth (MTPN) and inflammation (STAT family members) and chromatin remodeling (BRG1), and inhibition of proteins involved in hepatic differentiation (HNF4α) and reduction of fibrosis (SMAD7). The increase in mRNAs of four top upregulated genes including Reg3b, Aoc1, Tm4sf20 , and Cdx2 was confirmed at the protein level using immunohistochemistry. In conclusion, these studies indicate that a combination of increased inflammation, cell migration and wound healing, and inhibition of hepatic function, decreased antifibrotic gene expression are the major underlying pathogenic mechanisms in CHF/ARPKD.

Evaluation of galectin-3 and intestinal fatty acid binding protein as serum biomarkers in autosomal recessive polycystic kidney disease

BACKGROUND

Autosomal recessive polycystic kidney disease (ARPKD) causes fibrocystic kidney disease, congenital hepatic fibrosis, and portal hypertension. Serum galectin-3 (Gal-3) and intestinal fatty acid binding protein (I-FABP) are potential biomarkers of kidney fibrosis and portal hypertension, respectively. We examined whether serum Gal-3 associates with kidney disease severity and serum I-FABP associates with liver disease severity in ARPKD.

METHODS

Cross-sectional study of 29 participants with ARPKD (0.2-21 years old) and presence of native kidneys (Gal-3 analyses, n = 18) and/or native livers (I-FABP analyses, n = 21). Serum Gal-3 and I-FABP were analyzed using enzyme linked immunosorbent assay. Kidney disease severity variables included estimated glomerular filtration rate (eGFR) and height-adjusted total kidney volume (htTKV). Liver disease severity was characterized using ultrasound elastography to measure liver fibrosis, and spleen length and platelet count as markers of portal hypertension. Simple and multivariable linear regression examined associations between Gal-3 and kidney disease severity (adjusted for liver disease severity) and between I-FABP and liver disease severity (adjusted for eGFR).

RESULTS

Serum Gal-3 was negatively associated with eGFR; 1 standard deviation (SD) lower eGFR was associated with 0.795 SD higher Gal-3 level (95% CI - 1.116, - 0.473; p < 0.001). This association remained significant when adjusted for liver disease severity. Serum Gal-3 was not associated with htTKV in adjusted analyses. Overall I-FABP levels were elevated, but there were no linear associations between I-FABP and liver disease severity in unadjusted or adjusted models.

CONCLUSIONS

Serum Gal-3 is associated with eGFR in ARPKD, suggesting its value as a possible novel biomarker of kidney disease severity. We found no associations between serum I-FABP and ARPKD liver disease severity despite overall elevated I-FABP levels.

Congenital hepatic fibrosis with novel mutations in PKD1 gene masquerading as early cryptogenic cirrhosis: a rare case report

Background

Congenital hepatic fibrosis (CHF) is a rare disorder of the porto-biliary system occurring due to the defective remodeling of ductal architecture leading to progressive fibrosis of the portal tract. Though classically, CHF has been reported to be associated with autosomal recessive polycystic kidney disease (ARPKD), there have been only a few reports associating CHF with autosomal dominant polycystic kidney disease (ADPKD). Also, there is a lack of proper sequencing panels and gene database covering CHF-related genes in the medical literature. CHF often presents with features of portal hypertension without overt signs or symptoms of liver disease. However, often due to lack of awareness among radiologists and physicians, such cases might get labeled as early stage of cryptogenic cirrhosis.

Case presentation

Here, we report a 17-year-old boy who presented with a portal hypertensive bleed. Though initially an early phase of cirrhosis was suspected, no identifiable cause was found. Though he had grade IV esophageal varices, the liver function was absolutely normal with no signs of liver failure. This further leads to subsequent cross-sectional imagings which lead to the diagnosis of CHF. Further genetic analysis revealed it to be a rare case of CHF associated with ADPKD, with some novel mutations in the PKD1 gene.

Conclusion

CHF is a rare disorder needing a high index of suspicion and awareness. The presence of classic radiological morphological features of left lobe hypertrophy and right lobe atrophy with the tell-tale histopathological findings, fibrous enlargement of the portal tract, and irregularly shaped proliferating bile ducts often clinches the diagnosis.

Autosomal Recessive Polycystic Kidney Disease-The Clinical Aspects and Diagnostic Challenges

Autosomal recessive polycystic kidney disease (ARPKD) is one of the most common ciliopathies with kidney (nephromegaly, hypertension, renal dysfunction) and liver involvement (congenital hepatic fibrosis, dilated bile ducts). Clinical features also include growth failure and neurocognitive impairment. Plurality of clinical aspects requires multidisciplinary approach to treatment and care of patients. Until recently, diagnosis was based on clinical criteria. Results of genetic testing show the molecular basis of polycystic kidneys disease is heterogeneous, and differential diagnosis is essential. The aim of the article is to discuss the role of genetic testing and its difficulties in diagnostics of ARPKD in children.

Diagnosis of Congenital Hepatic Fibrosis in Adulthood

OBJECTIVES

We studied clinicopathologic features of congenital hepatic fibrosis (CHF) that could aid the diagnosis of this relatively rare condition during adulthood.

METHODS

Five consecutive adult CHF cases were identified in a single institution.

RESULTS

Clinical manifestations of CHF varied from asymptomatic to requiring liver transplantation. Three of five cases had other disease associations, including Joubert syndrome, Caroli disease, polycystic kidney disease, and congenital anomaly of hepatic vasculature. No unique common radiologic findings were found. Histologically, all cases showed characteristic abnormal interlobular bile ducts embedded in fibrotic portal stroma, with varying degrees of liver fibrosis.

CONCLUSIONS

While other disease associations and characteristic liver histomorphology are helpful clues to suspect the diagnosis of CHF in adult patients, other differential diagnoses should be excluded clinically and radiologically. This study highlights the importance of a multidisciplinary diagnostic approach by pathologists, radiologists, and hepatologists for the accurate diagnosis of CHF during adulthood.

Prenatal MR imaging features of Caroli syndrome in association with autosomal recessive polycystic kidney disease

Caroli syndrome, which is characterized by saccular and fusiform dilatation of the biliary ducts, is usually observed in association with autosomal recessive polycystic kidney disease (ARPKD). Although the diagnosis of ARPKD is generally easy to make in postnatal ultrasound, the diagnosis of Caroli syndrome may be challenging in prenatal ultrasound. Herein, we present a case of a 29-week fetus with ARPKD associated with Caroli syndrome in whom fetal magnetic resonance imaging was essential to identify the “central dot sign” within the dilated biliary ducts to confirm the prenatal diagnosis of Caroli syndrome and to increase our level of confidence in this diagnosis.

CONGENITAL HEPATIC FIBROSIS AND OBLITERATIVE PORTAL VENOPATHY WITHOUT PORTAL HYPERTENSION - A REVIEW OF LITERATURE BASED ON AN ASYMPTOMATIC CASE

The disease and the case reported here are relevant especially because of their varied clinical presentation, possibility of being associated with other disorders affecting several organs and possible differential diagnoses. Congenital Hepatic Fibrosis is an autosomal recessive disease due to mutation in the PKHD1 gene, which encodes the fibrocystin/polyductine protein. It is a cholangiopathy, characterized by varying degrees of periportal fibrosis and irregular proliferation of bile ducts. Affected patients are typically diagnosed in childhood, but in some cases the disease may remain asymptomatic for many years. The exact prevalence and incidence of the disease are not known, but it is consider a rare disease, with a few hundred cases described worldwide. It can affect all ethnic groups and occur associated with various hereditary and non-hereditary disorders. The clinical presentation is quite variable, with melena and hematemesis being initial symptoms in 30%-70% of the cases. More rarely, they may present episodes of cholangitis. The disease has been classified into four types: portal hypertension, cholestasis / cholangitis, mixed and latent. Diagnosis begins with imaging tests, but the definition is made by the histopathological sample. So far, there is no specific therapy that can stop or reverse the pathological process. Currently, the therapeutic strategy is to treat the complications of the disease.

Increased YAP Activation Is Associated With Hepatic Cyst Epithelial Cell Proliferation in ARPKD/CHF

Autosomal recessive polycystic kidney disease/congenital hepatic fibrosis (ARPKD/CHF) is a rare but fatal genetic disease characterized by progressive cyst development in the kidneys and liver. Liver cysts arise from aberrantly proliferative cholangiocytes accompanied by pericystic fibrosis and inflammation. Yes-associated protein (YAP), the downstream effector of the Hippo signaling pathway, is implicated in human hepatic malignancies such as hepatocellular carcinoma, cholangiocarcinoma, and hepatoblastoma, but its role in hepatic cystogenesis in ARPKD/CHF is unknown. We studied the role of the YAP in hepatic cyst development using polycystic kidney (PCK) rats, an orthologous model of ARPKD, and in human ARPKD/CHF patients. The liver cyst wall epithelial cells (CWECs) in PCK rats were highly proliferative and exhibited expression of YAP. There was increased expression of YAP target genes, Ccnd1 (cyclin D1) and Ctgf (connective tissue growth factor), in PCK rat livers. Extensive expression of YAP and its target genes was also detected in human ARPKD/CHF liver samples. Finally, pharmacological inhibition of YAP activity with verteporfin and short hairpin (sh) RNA-mediated knockdown of YAP expression in isolated liver CWECs significantly reduced their proliferation. These data indicate that increased YAP activity, possibly through dysregulation of the Hippo signaling pathway, is associated with hepatic cyst growth in ARPKD/CHF.

Diagnosis and Management of Hepatobiliary Complications in Autosomal Recessive Polycystic Kidney Disease

Autosomal recessive polycystic kidney disease (ARPKD) is a congenital hepatorenal fibrocystic disease. The hepatic manifestations of ARPKD can range from asymptomatic to portal hypertension and massively dilated biliary system that results in liver transplantation. Hepatic complications of ARPKD typically present with signs of portal hypertension (splenomegaly and thrombocytopenia) or cholangitis. Liver disease in ARPKD does not always correlate with severity of renal disease. Management of ARPKD-related liver disease is largely treating specific symptoms, such as antibiotics for cholangitis or endoscopic treatment for variceal bleeding. If complications cannot be managed medically, liver transplantation may be indicated. This mini-review will discuss the clinical manifestations and management of children with ARPKD liver disease.

Evidence for a "Pathogenic Triumvirate" in Congenital Hepatic Fibrosis in Autosomal Recessive Polycystic Kidney Disease

Autosomal recessive polycystic kidney disease (ARPKD) is a severe monogenic disorder that occurs due to mutations in the PKHD1 gene. Congenital hepatic fibrosis (CHF) associated with ARPKD is characterized by the presence of hepatic cysts derived from dilated bile ducts and a robust, pericystic fibrosis. Cyst growth, due to cyst wall epithelial cell hyperproliferation and fluid secretion, is thought to be the driving force behind disease progression. Liver fibrosis is a wound healing response in which collagen accumulates in the liver due to an imbalance between extracellular matrix synthesis and degradation. Whereas both hyperproliferation and pericystic fibrosis are hallmarks of CHF/ARPKD, whether or not these two processes influence one another remains unclear. Additionally, recent studies demonstrate that inflammation is a common feature of CHF/ARPKD. Therefore, we propose a "pathogenic triumvirate" consisting of hyperproliferation of cyst wall growth, pericystic fibrosis, and inflammation which drives CHF/ARPKD progression. This review will summarize what is known regarding the mechanisms of cyst growth, fibrosis, and inflammation in CHF/ARPKD. Further, we will discuss the potential advantage of identifying a core pathogenic feature in CHF/ARPKD to aid in the development of novel therapeutic approaches. If a core pathogenic feature does not exist, then developing multimodality therapeutic approaches to target each member of the "pathogenic triumvirate" individually may be a better strategy to manage this debilitating disease.

Magnetic resonance microscopy of renal and biliary abnormalities in excised tissues from a mouse model of autosomal recessive polycystic kidney disease

Polycystic kidney disease (PKD) is transmitted as either an autosomal dominant or recessive trait and is a major cause of renal failure and liver fibrosis. The cpk mouse model of autosomal recessive PKD (ARPKD) has been extensively characterized using standard histopathological techniques after euthanasia. In the current study, we sought to validate magnetic resonance microscopy (MRM) as a robust tool for assessing the ARPKD phenotype. We used MRM to evaluate the liver and kidney of wild-type and cpk animals at resolutions <100 μm and generated three-dimensional (3D) renderings for pathological evaluation. Our study demonstrates that MRM is an excellent method for evaluating the complex, 3D structural defects in this ARPKD mouse model. We found that MRM was equivalent to water displacement in assessing kidney volume. Additionally, using MRM we demonstrated for the first time that the cpk liver exhibits less extensive ductal arborization, that it was reduced in volume, and that the ductal volume was disproportionately smaller. Histopathology indicates that this is a consequence of bile duct malformation. With its reduced processing time, volumetric information, and 3D capabilities, MRM will be a useful tool for future in vivo and longitudinal studies of disease progression in ARPKD. In addition, MRM will provide a unique tool to determine whether the human disease shares the newly appreciated features of the murine biliary phenotype.

Caroli's disease misdiagnosed as intraductal papillary neoplasm of the bile duct

Caroli's disease is a rare autosomal-recessive disorder caused by malformation of the ductal plate during embryonic development. Although it is present at birth, Caroli's disease is typically not diagnosed until between the second and fourth decades of life, as it was in the present patient. Here we report a rare case of Caroli's disease limited to one liver segment, which was initially misdiagnosed as an intraductal papillary neoplasm of the bile duct. The asymptomatic patient was treated with liver segmentectomy.

Feeding soy protein isolate and n-3 PUFA affects polycystic liver disease progression in a PCK rat model of autosomal polycystic kidney disease

OBJECTIVE

In polycystic liver disease (PCLD), multiple cysts cause liver enlargement, structural damage, and loss of function. Soy protein and dietary ω-3 polyunsaturated fatty acids (n-3 PUFAs) have been found to decrease cyst proliferation and inflammation in polycystic kidney disease. Therefore, the aim of the study was to investigate whether soy protein and n-3 PUFA supplementation attenuates PCLD.

METHODS

Young (age 28 days) female PCK rats were fed (n = 12 per group) either casein + corn oil (casein + CO), casein + soybean oil (casein + SO), soy protein isolate + soybean oil (SPI + SO), or SPI + 1:1 soybean/salmon oil blend (SPI + SB) diet for 12 weeks. Liver histology, gene expression by real-time quantitative polymerase chain reaction, and serum markers of liver injury were determined.

RESULTS

Diet had no effect on PCLD progression as indicated by no significant differences in liver weight and hepatic proliferation gene expression between diet groups. PCK rats fed SPI + SB diet, however, had the greatest (P < 0.05) histological evidence of hepatic cyst obstruction, portal inflammation, steatosis, and upregulation (P = 0.03) of fibrosis-related genes. Rats fed SPI + SB diet also had the lowest (P < 0.001) serum cholesterol and higher (P < 0.05) serum alkaline phosphatase and bilirubin concentrations.

CONCLUSIONS

Feeding young female PCK rats SPI and n-3 PUFA failed to attenuate PCLD progression. Furthermore, feeding SPI + SB diet resulted in complications of hepatic steatosis attributable to cysts obstruction of bile duct and hepatic vein. Based on the results, it was concluded that diet intervention alone was not effective at attenuating PCLD associated with autosomal recessive polycystic kidney disease.

From the radiologic pathology archives: pediatric polycystic kidney disease and other ciliopathies: radiologic-pathologic correlation

Genetic defects of cilia cause a wide range of diseases, collectively known as ciliopathies. Primary, or nonmotile, cilia function as sensory organelles involved in the regulation of cell growth, differentiation, and homeostasis. Cilia are present in nearly every cell in the body and mutations of genes encoding ciliary proteins affect multiple organs, including the kidneys, liver, pancreas, retina, central nervous system (CNS), and skeletal system. Genetic mutations causing ciliary dysfunction result in a large number of heterogeneous phenotypes that can manifest with a variety of overlapping abnormalities in multiple organ systems. Renal manifestations of ciliopathies are the most common abnormalities and include collecting duct dilatation and cyst formation in autosomal recessive polycystic kidney disease (ARPKD), cyst formation anywhere in the nephron in autosomal dominant polycystic kidney disease (ADPKD), and tubulointerstitial fibrosis in nephronophthisis, as well as in several CNS and skeletal malformation syndromes. Hepatic disease is another common manifestation of ciliopathies, ranging from duct dilatation and cyst formation in ARPKD and ADPKD to periportal fibrosis in ARPKD and several malformation syndromes. The unifying molecular pathogenesis of this emerging class of disorders explains the overlap of abnormalities in disparate organ systems and links diseases of widely varied clinical features. It is important for radiologists to be able to recognize the multisystem manifestations of these syndromes, as imaging plays an important role in diagnosis and follow-up of affected patients.

Segmental cholangiectasia clinically worrisome for cholangiocarcinoma: comparison with recurrent pyogenic cholangitis

The aim of this study was to review the clinical, radiographic, and pathologic features of cases of benign segmental cholangiectasia in non-Asian US patients with clinical concern for cholangiocarcinoma and compare these features with cases of recurrent pyogenic cholangitis (RPC) in Asian patients. A total of 10 non-Asian US patients with benign segmental cholangiectasia were included in this study. Nine of them underwent partial hepatic resection due to cholangiographic findings of segmental cholangiectasia with mural thickening and/or proximal biliary stricture. One was found to have markedly dilated and thickened intrahepatic bile ducts at the time of autopsy. Clinical and radiographic findings were reviewed. Elastin stains and immunostains for immunoglobulin G4, cluster of differentiation (CD1a), and Langerin were performed. Six comparison cases of RPC in Asian US patients were also examined. Histologic examination of resection specimens revealed markedly dilated large intrahepatic bile ducts with variable degrees of mural fibrosis, periductal gland hyperplasia, inflammation, and liver parenchymal atrophy. These changes were not associated with a ductular reaction. There was no evidence of biliary dysplasia or biliary cirrhosis in any cases. No gross or microscopic feature definitively separated the Asian from non-Asian patients. The etiology of this disorder in non-Asian US patients is unclear. It does not appear to represent a localized variant of Caroli disease or primary sclerosing cholangitis. The high degree of similarity shared by these cases and classic RPC suggests a common pathogenic mechanism, although the pathologic features tend to be less well developed in the cases from the non-Asian US patients.

Autosomal recessive polycystic kidney disease: a hepatorenal fibrocystic disorder with pleiotropic effects

Autosomal recessive polycystic kidney disease (ARPKD) is an important cause of chronic kidney disease in children. The care of ARPKD patients has traditionally been the realm of pediatric nephrologists; however, the disease has multisystem effects, and a comprehensive care strategy often requires a multidisciplinary team. Most notably, ARPKD patients have congenital hepatic fibrosis, which can lead to portal hypertension, requiring close follow-up by pediatric gastroenterologists. In severely affected infants, the diagnosis is often first suspected by obstetricians detecting enlarged, echogenic kidneys and oligohydramnios on prenatal ultrasounds. Neonatologists are central to the care of these infants, who may have respiratory compromise due to pulmonary hypoplasia and massively enlarged kidneys. Surgical considerations can include the possibility of nephrectomy to relieve mass effect, placement of dialysis access, and kidney and/or liver transplantation. Families of patients with ARPKD also face decisions regarding genetic testing of affected children, testing of asymptomatic siblings, or consideration of preimplantation genetic diagnosis for future pregnancies. They may therefore interface with genetic counselors, geneticists, and reproductive endocrinologists. Children with ARPKD may also be at risk for neurocognitive dysfunction and may require neuropsychological referral. The care of patients and families affected by ARPKD is therefore a multidisciplinary effort, and the general pediatrician can play a central role in this complex web of care. In this review, we outline the spectrum of clinical manifestations of ARPKD and review genetics of the disease, clinical and genetic diagnosis, perinatal management, management of organ-specific complications, and future directions for disease monitoring and potential therapies.

Liver involvement in children with ciliopathies

Abnormalities in primary cilia lead to diseases called ciliopathies. Multiple organ involvement is the norm since primary cilia are present in most cells. When cholangiocyte cilia are abnormal, ductal plate malformation ensues leading to such conditions as congenital hepatic fibrosis, Caroli disease or syndrome, or other fibrocystic disease.

MALDI imaging MS reveals candidate lipid markers of polycystic kidney disease

Autosomal recessive polycystic kidney disease (ARPKD) is a severe, monogenetically inherited kidney and liver disease. PCK rats carrying the orthologous mutant gene serve as a model of human disease, and alterations in lipid profiles in PCK rats suggest that defined subsets of lipids may be useful as molecular disease markers. Whereas MALDI protein imaging mass spectrometry (IMS) has become a promising tool for disease classification, widely applicable workflows that link MALDI lipid imaging and identification as well as structural characterization of candidate disease-classifying marker lipids are lacking. Here, we combine selective MALDI imaging of sulfated kidney lipids and Fisher discriminant analysis (FDA) of imaging data sets for identification of candidate markers of progressive disease in PCK rats. Our study highlights strong increases in lower mass lipids as main classifiers of cystic disease. Structure determination by high-resolution mass spectrometry identifies these altered lipids as taurine-conjugated bile acids. These sulfated lipids are selectively elevated in the PCK rat model but not in models of related hepatorenal fibrocystic diseases, suggesting that they be molecular markers of the disease and that a combination of MALDI imaging with high-resolution MS methods and Fisher discriminant data analysis may be applicable for lipid marker discovery.

New approaches to the autosomal recessive polycystic kidney disease patient with dual kidney-liver complications

Improved neonatal medical care and renal replacement technology have improved the long-term survival of patients with ARPKD. Ten-yr survival of those surviving the first year of life is reported to be 82% and is continuing to improve further. However, despite increases in overall survival and improved treatment of systemic hypertension and other complications of their renal disease, nearly 50% of survivors will develop ESRD within the first decade of life. In addition to renal pathology, patients with ARPKD develop ductal plate malformations with cystic dilation of intra- and extrahepatic bile ducts resulting in CHF and Caroli syndrome. Many patients with CHF will develop portal hypertension with resulting esophageal varices, splenomegaly, hypersplenism, protein losing enteropathy, and gastrointestinal bleeding. Management of portal hypertension may require EBL of esophageal varices or porto-systemic shunting. Complications of hepatic involvement can include ascending cholangitis, cholestasis with malabsorption of fat-soluble vitamins, and rarely benign or malignant liver tumors. Patients with ARPKD who eventually reach ESRD, and ultimately require kidney transplantation, present a unique set of complications related to their underlying hepato-biliary disease. In this review, we focus on new approaches to these challenging patients, including the indications for liver transplantation in ARPKD patients with severe chronic kidney disease awaiting kidney transplant. While survival in patients with ARPKD and isolated kidney transplant is comparable to that of age-matched pediatric patients who have received kidney transplants due to other primary renal diseases, 64-80% of the mortality occurring in ARPKD kidney transplant patients is attributed to cholangitis/sepsis, which is related to their hepato-biliary disease. Recent data demonstrate that surgical mortality among pediatric liver transplant recipients is decreased to <10% at one yr. The immunosuppressive regimen used for kidney transplant recipients is adequate for most liver transplant recipients. We therefore suggest that in a select group of ARPKD patients with recurrent cholangitis or complications of portal hypertension, combined liver-kidney transplant is a viable option. Although further study is necessary to confirm our approach, we believe that combined liver-kidney transplantation can potentially decrease overall mortality and morbidity in carefully selected ARPKD patients with ESRD and clinically significant CHF.